/* ====================================================================
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2002-2003 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowledgement:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgement may appear in the software itself,
 *    if and wherever such third-party acknowledgements normally appear.
 *
 * 4. The names "The Jakarta Project", "Commons", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */
package org.hibernate.exception;

import org.hibernate.util.ArrayHelper;

import java.io.PrintStream;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.LinkedList;
import java.util.List;
import java.util.StringTokenizer;

/**
 * <p>Provides utilities for manipulating and examining
 * <code>Throwable</code> objects.</p>
 *
 * @author <a href="mailto:dlr@finemaltcoding.com">Daniel Rall</a>
 * @author Dmitri Plotnikov
 * @author Stephen Colebourne
 * @author <a href="mailto:ggregory@seagullsw.com">Gary Gregory</a>
 * @author Pete Gieser
 * @version $Id: ExceptionUtils.java 4782 2004-11-21 00:11:27Z pgmjsd $
 * @since 1.0
 */
public final class ExceptionUtils {

	private static final String LINE_SEPARATOR = System.getProperty( "line.separator" );

	/**
	 * <p>Used when printing stack frames to denote the start of a
	 * wrapped exception.</p>
	 * <p/>
	 * <p>Package private for accessibility by test suite.</p>
	 */
	static final String WRAPPED_MARKER = " [wrapped] ";

	/**
	 * <p>The names of methods commonly used to access a wrapped exception.</p>
	 */
	private static final String[] CAUSE_METHOD_NAMES = {
		"getCause",
		"getNextException",
		"getTargetException",
		"getException",
		"getSourceException",
		"getRootCause",
		"getCausedByException",
		"getNested"
	};

	/**
	 * <p>The Method object for JDK1.4 getCause.</p>
	 */
	private static final Method THROWABLE_CAUSE_METHOD;

	static {
		Method getCauseMethod;
		try {
			getCauseMethod = Throwable.class.getMethod( "getCause", null );
		}
		catch ( Exception e ) {
			getCauseMethod = null;
		}
		THROWABLE_CAUSE_METHOD = getCauseMethod;
	}

	private ExceptionUtils() {
	}

	//-----------------------------------------------------------------------
	/**
	 * <p>Adds to the list of method names used in the search for <code>Throwable</code>
	 * objects.</p>
	 *
	 * @param methodName  the methodName to add to the list, <code>null</code>
	 *  and empty strings are ignored
	 * @since 2.0
	 */
	/*public static void addCauseMethodName(String methodName) {
		if ( StringHelper.isNotEmpty(methodName) ) {
			List list = new ArrayList( Arrays.asList(CAUSE_METHOD_NAMES );
			list.add(methodName);
			CAUSE_METHOD_NAMES = (String[]) list.toArray(new String[list.size()]);
		}
	}*/

	/**
	 * <p>Introspects the <code>Throwable</code> to obtain the cause.</p>
	 * <p/>
	 * <p>The method searches for methods with specific names that return a
	 * <code>Throwable</code> object. This will pick up most wrapping exceptions,
	 * including those from JDK 1.4, and
	 * {@link org.apache.commons.lang.exception.NestableException NestableException}.
	 * The method names can be added to using {@link #addCauseMethodName(String)}.</p>
	 * <p/>
	 * <p>The default list searched for are:</p>
	 * <ul>
	 * <li><code>getCause()</code></li>
	 * <li><code>getNextException()</code></li>
	 * <li><code>getTargetException()</code></li>
	 * <li><code>getException()</code></li>
	 * <li><code>getSourceException()</code></li>
	 * <li><code>getRootCause()</code></li>
	 * <li><code>getCausedByException()</code></li>
	 * <li><code>getNested()</code></li>
	 * </ul>
	 * <p/>
	 * <p>In the absence of any such method, the object is inspected for a
	 * <code>detail</code> field assignable to a <code>Throwable</code>.</p>
	 * <p/>
	 * <p>If none of the above is found, returns <code>null</code>.</p>
	 *
	 * @param throwable the throwable to introspect for a cause, may be null
	 * @return the cause of the <code>Throwable</code>,
	 *         <code>null</code> if none found or null throwable input
	 */
	public static Throwable getCause(Throwable throwable) {
		return getCause( throwable, CAUSE_METHOD_NAMES );
	}

	/**
	 * <p>Introspects the <code>Throwable</code> to obtain the cause.</p>
	 * <p/>
	 * <ol>
	 * <li>Try known exception types.</li>
	 * <li>Try the supplied array of method names.</li>
	 * <li>Try the field 'detail'.</li>
	 * </ol>
	 * <p/>
	 * <p>A <code>null</code> set of method names means use the default set.
	 * A <code>null</code> in the set of method names will be ignored.</p>
	 *
	 * @param throwable   the throwable to introspect for a cause, may be null
	 * @param methodNames the method names, null treated as default set
	 * @return the cause of the <code>Throwable</code>,
	 *         <code>null</code> if none found or null throwable input
	 */
	public static Throwable getCause(Throwable throwable, String[] methodNames) {
		if ( throwable == null ) {
			return null;
		}
		Throwable cause = getCauseUsingWellKnownTypes( throwable );
		if ( cause == null ) {
			if ( methodNames == null ) {
				methodNames = CAUSE_METHOD_NAMES;
			}
			for ( int i = 0; i < methodNames.length; i++ ) {
				String methodName = methodNames[i];
				if ( methodName != null ) {
					cause = getCauseUsingMethodName( throwable, methodName );
					if ( cause != null ) {
						break;
					}
				}
			}

			if ( cause == null ) {
				cause = getCauseUsingFieldName( throwable, "detail" );
			}
		}
		return cause;
	}

	/**
	 * <p>Introspects the <code>Throwable</code> to obtain the root cause.</p>
	 * <p/>
	 * <p>This method walks through the exception chain to the last element,
	 * "root" of the tree, using {@link #getCause(Throwable)}, and
	 * returns that exception.</p>
	 *
	 * @param throwable the throwable to get the root cause for, may be null
	 * @return the root cause of the <code>Throwable</code>,
	 *         <code>null</code> if none found or null throwable input
	 */
	public static Throwable getRootCause(Throwable throwable) {
		Throwable cause = getCause( throwable );
		if ( cause != null ) {
			throwable = cause;
			while ( ( throwable = getCause( throwable ) ) != null ) {
				cause = throwable;
			}
		}
		return cause;
	}

	/**
	 * <p>Finds a <code>Throwable</code> for known types.</p>
	 * <p/>
	 * <p>Uses <code>instanceof</code> checks to examine the exception,
	 * looking for well known types which could contain chained or
	 * wrapped exceptions.</p>
	 *
	 * @param throwable the exception to examine
	 * @return the wrapped exception, or <code>null</code> if not found
	 */
	private static Throwable getCauseUsingWellKnownTypes(Throwable throwable) {
		if ( throwable instanceof Nestable ) {
			return ( ( Nestable ) throwable ).getCause();
		}
		else if ( throwable instanceof SQLException ) {
			return ( ( SQLException ) throwable ).getNextException();
		}
		else if ( throwable instanceof InvocationTargetException ) {
			return ( ( InvocationTargetException ) throwable ).getTargetException();
		}
		else {
			return null;
		}
	}

	/**
	 * <p>Finds a <code>Throwable</code> by method name.</p>
	 *
	 * @param throwable  the exception to examine
	 * @param methodName the name of the method to find and invoke
	 * @return the wrapped exception, or <code>null</code> if not found
	 */
	private static Throwable getCauseUsingMethodName(Throwable throwable, String methodName) {
		Method method = null;
		try {
			method = throwable.getClass().getMethod( methodName, null );
		}
		catch ( NoSuchMethodException ignored ) {
		}
		catch ( SecurityException ignored ) {
		}

		if ( method != null && Throwable.class.isAssignableFrom( method.getReturnType() ) ) {
			try {
				return ( Throwable ) method.invoke( throwable, ArrayHelper.EMPTY_OBJECT_ARRAY );
			}
			catch ( IllegalAccessException ignored ) {
			}
			catch ( IllegalArgumentException ignored ) {
			}
			catch ( InvocationTargetException ignored ) {
			}
		}
		return null;
	}

	/**
	 * <p>Finds a <code>Throwable</code> by field name.</p>
	 *
	 * @param throwable the exception to examine
	 * @param fieldName the name of the attribute to examine
	 * @return the wrapped exception, or <code>null</code> if not found
	 */
	private static Throwable getCauseUsingFieldName(Throwable throwable, String fieldName) {
		Field field = null;
		try {
			field = throwable.getClass().getField( fieldName );
		}
		catch ( NoSuchFieldException ignored ) {
		}
		catch ( SecurityException ignored ) {
		}

		if ( field != null && Throwable.class.isAssignableFrom( field.getType() ) ) {
			try {
				return ( Throwable ) field.get( throwable );
			}
			catch ( IllegalAccessException ignored ) {
			}
			catch ( IllegalArgumentException ignored ) {
			}
		}
		return null;
	}

	//-----------------------------------------------------------------------
	/**
	 * <p>Checks if the Throwable class has a <code>getCause</code> method.</p>
	 * <p/>
	 * <p>This is true for JDK 1.4 and above.</p>
	 *
	 * @return true if Throwable is nestable
	 * @since 2.0
	 */
	public static boolean isThrowableNested() {
		return ( THROWABLE_CAUSE_METHOD != null );
	}

	/**
	 * <p>Checks whether this <code>Throwable</code> class can store a cause.</p>
	 * <p/>
	 * <p>This method does <b>not</b> check whether it actually does store a cause.<p>
	 *
	 * @param throwable the <code>Throwable</code> to examine, may be null
	 * @return boolean <code>true</code> if nested otherwise <code>false</code>
	 * @since 2.0
	 */
	public static boolean isNestedThrowable(Throwable throwable) {
		if ( throwable == null ) {
			return false;
		}

		if ( throwable instanceof Nestable ) {
			return true;
		}
		else if ( throwable instanceof SQLException ) {
			return true;
		}
		else if ( throwable instanceof InvocationTargetException ) {
			return true;
		}
		else if ( isThrowableNested() ) {
			return true;
		}

		Class cls = throwable.getClass();
		for ( int i = 0, isize = CAUSE_METHOD_NAMES.length; i < isize; i++ ) {
			try {
				Method method = cls.getMethod( CAUSE_METHOD_NAMES[i], null );
				if ( method != null && Throwable.class.isAssignableFrom( method.getReturnType() ) ) {
					return true;
				}
			}
			catch ( NoSuchMethodException ignored ) {
			}
			catch ( SecurityException ignored ) {
			}
		}

		try {
			Field field = cls.getField( "detail" );
			if ( field != null ) {
				return true;
			}
		}
		catch ( NoSuchFieldException ignored ) {
		}
		catch ( SecurityException ignored ) {
		}

		return false;
	}

	//-----------------------------------------------------------------------
	/**
	 * <p>Counts the number of <code>Throwable</code> objects in the
	 * exception chain.</p>
	 * <p/>
	 * <p>A throwable without cause will return <code>1</code>.
	 * A throwable with one cause will return <code>2</code> and so on.
	 * A <code>null</code> throwable will return <code>0</code>.</p>
	 *
	 * @param throwable the throwable to inspect, may be null
	 * @return the count of throwables, zero if null input
	 */
	public static int getThrowableCount(Throwable throwable) {
		int count = 0;
		while ( throwable != null ) {
			count++;
			throwable = ExceptionUtils.getCause( throwable );
		}
		return count;
	}

	/**
	 * <p>Returns the list of <code>Throwable</code> objects in the
	 * exception chain.</p>
	 * <p/>
	 * <p>A throwable without cause will return an array containing
	 * one element - the input throwable.
	 * A throwable with one cause will return an array containing
	 * two elements. - the input throwable and the cause throwable.
	 * A <code>null</code> throwable will return an array size zero.</p>
	 *
	 * @param throwable the throwable to inspect, may be null
	 * @return the array of throwables, never null
	 */
	public static Throwable[] getThrowables(Throwable throwable) {
		List list = new ArrayList();
		while ( throwable != null ) {
			list.add( throwable );
			throwable = ExceptionUtils.getCause( throwable );
		}
		return ( Throwable[] ) list.toArray( new Throwable[list.size()] );
	}

	//-----------------------------------------------------------------------
	/**
	 * <p>Returns the (zero based) index of the first <code>Throwable</code>
	 * that matches the specified type in the exception chain.</p>
	 * <p/>
	 * <p>A <code>null</code> throwable returns <code>-1</code>.
	 * A <code>null</code> type returns <code>-1</code>.
	 * No match in the chain returns <code>-1</code>.</p>
	 *
	 * @param throwable the throwable to inspect, may be null
	 * @param type      the type to search for
	 * @return the index into the throwable chain, -1 if no match or null input
	 */
	public static int indexOfThrowable(Throwable throwable, Class type) {
		return indexOfThrowable( throwable, type, 0 );
	}

	/**
	 * <p>Returns the (zero based) index of the first <code>Throwable</code>
	 * that matches the specified type in the exception chain from
	 * a specified index.</p>
	 * <p/>
	 * <p>A <code>null</code> throwable returns <code>-1</code>.
	 * A <code>null</code> type returns <code>-1</code>.
	 * No match in the chain returns <code>-1</code>.
	 * A negative start index is treated as zero.
	 * A start index greater than the number of throwables returns <code>-1</code>.</p>
	 *
	 * @param throwable the throwable to inspect, may be null
	 * @param type      the type to search for
	 * @param fromIndex the (zero based) index of the starting position,
	 *                  negative treated as zero, larger than chain size returns -1
	 * @return the index into the throwable chain, -1 if no match or null input
	 */
	public static int indexOfThrowable(Throwable throwable, Class type, int fromIndex) {
		if ( throwable == null ) {
			return -1;
		}
		if ( fromIndex < 0 ) {
			fromIndex = 0;
		}
		Throwable[] throwables = ExceptionUtils.getThrowables( throwable );
		if ( fromIndex >= throwables.length ) {
			return -1;
		}
		for ( int i = fromIndex; i < throwables.length; i++ ) {
			if ( throwables[i].getClass().equals( type ) ) {
				return i;
			}
		}
		return -1;
	}

	//-----------------------------------------------------------------------
	/**
	 * <p>Prints a compact stack trace for the root cause of a throwable
	 * to <code>System.err</code>.</p>
	 * <p/>
	 * <p>The compact stack trace starts with the root cause and prints
	 * stack frames up to the place where it was caught and wrapped.
	 * Then it prints the wrapped exception and continues with stack frames
	 * until the wrapper exception is caught and wrapped again, etc.</p>
	 * <p/>
	 * <p>The method is equivalent to <code>printStackTrace</code> for throwables
	 * that don't have nested causes.</p>
	 *
	 * @param throwable the throwable to output
	 * @since 2.0
	 */
	public static void printRootCauseStackTrace(Throwable throwable) {
		printRootCauseStackTrace( throwable, System.err );
	}

	/**
	 * <p>Prints a compact stack trace for the root cause of a throwable.</p>
	 * <p/>
	 * <p>The compact stack trace starts with the root cause and prints
	 * stack frames up to the place where it was caught and wrapped.
	 * Then it prints the wrapped exception and continues with stack frames
	 * until the wrapper exception is caught and wrapped again, etc.</p>
	 * <p/>
	 * <p>The method is equivalent to <code>printStackTrace</code> for throwables
	 * that don't have nested causes.</p>
	 *
	 * @param throwable the throwable to output, may be null
	 * @param stream    the stream to output to, may not be null
	 * @throws IllegalArgumentException if the stream is <code>null</code>
	 * @since 2.0
	 */
	public static void printRootCauseStackTrace(Throwable throwable, PrintStream stream) {
		if ( throwable == null ) {
			return;
		}
		if ( stream == null ) {
			throw new IllegalArgumentException( "The PrintStream must not be null" );
		}
		String trace[] = getRootCauseStackTrace( throwable );
		for ( int i = 0; i < trace.length; i++ ) {
			stream.println( trace[i] );
		}
		stream.flush();
	}

	/**
	 * <p>Prints a compact stack trace for the root cause of a throwable.</p>
	 * <p/>
	 * <p>The compact stack trace starts with the root cause and prints
	 * stack frames up to the place where it was caught and wrapped.
	 * Then it prints the wrapped exception and continues with stack frames
	 * until the wrapper exception is caught and wrapped again, etc.</p>
	 * <p/>
	 * <p>The method is equivalent to <code>printStackTrace</code> for throwables
	 * that don't have nested causes.</p>
	 *
	 * @param throwable the throwable to output, may be null
	 * @param writer    the writer to output to, may not be null
	 * @throws IllegalArgumentException if the writer is <code>null</code>
	 * @since 2.0
	 */
	public static void printRootCauseStackTrace(Throwable throwable, PrintWriter writer) {
		if ( throwable == null ) {
			return;
		}
		if ( writer == null ) {
			throw new IllegalArgumentException( "The PrintWriter must not be null" );
		}
		String trace[] = getRootCauseStackTrace( throwable );
		for ( int i = 0; i < trace.length; i++ ) {
			writer.println( trace[i] );
		}
		writer.flush();
	}

	//-----------------------------------------------------------------------
	/**
	 * <p>Creates a compact stack trace for the root cause of the supplied
	 * <code>Throwable</code>.</p>
	 *
	 * @param throwable the throwable to examine, may be null
	 * @return an array of stack trace frames, never null
	 * @since 2.0
	 */
	public static String[] getRootCauseStackTrace(Throwable throwable) {
		if ( throwable == null ) {
			return ArrayHelper.EMPTY_STRING_ARRAY;
		}
		Throwable throwables[] = getThrowables( throwable );
		int count = throwables.length;
		ArrayList frames = new ArrayList();
		List nextTrace = getStackFrameList( throwables[count - 1] );
		for ( int i = count; --i >= 0; ) {
			List trace = nextTrace;
			if ( i != 0 ) {
				nextTrace = getStackFrameList( throwables[i - 1] );
				removeCommonFrames( trace, nextTrace );
			}
			if ( i == count - 1 ) {
				frames.add( throwables[i].toString() );
			}
			else {
				frames.add( WRAPPED_MARKER + throwables[i].toString() );
			}
			for ( int j = 0; j < trace.size(); j++ ) {
				frames.add( trace.get( j ) );
			}
		}
		return ( String[] ) frames.toArray( new String[0] );
	}

	/**
	 * <p>Removes common frames from the cause trace given the two stack traces.</p>
	 *
	 * @param causeFrames   stack trace of a cause throwable
	 * @param wrapperFrames stack trace of a wrapper throwable
	 * @throws IllegalArgumentException if either argument is null
	 * @since 2.0
	 */
	public static void removeCommonFrames(List causeFrames, List wrapperFrames) {
		if ( causeFrames == null || wrapperFrames == null ) {
			throw new IllegalArgumentException( "The List must not be null" );
		}
		int causeFrameIndex = causeFrames.size() - 1;
		int wrapperFrameIndex = wrapperFrames.size() - 1;
		while ( causeFrameIndex >= 0 && wrapperFrameIndex >= 0 ) {
			// Remove the frame from the cause trace if it is the same
			// as in the wrapper trace
			String causeFrame = ( String ) causeFrames.get( causeFrameIndex );
			String wrapperFrame = ( String ) wrapperFrames.get( wrapperFrameIndex );
			if ( causeFrame.equals( wrapperFrame ) ) {
				causeFrames.remove( causeFrameIndex );
			}
			causeFrameIndex--;
			wrapperFrameIndex--;
		}
	}

	//-----------------------------------------------------------------------
	/**
	 * <p>Gets the stack trace from a Throwable as a String.</p>
	 *
	 * @param throwable the <code>Throwable</code> to be examined
	 * @return the stack trace as generated by the exception's
	 *         <code>printStackTrace(PrintWriter)</code> method
	 */
	public static String getStackTrace(Throwable throwable) {
		StringWriter sw = new StringWriter();
		PrintWriter pw = new PrintWriter( sw, true );
		throwable.printStackTrace( pw );
		return sw.getBuffer().toString();
	}

	/**
	 * <p>A way to get the entire nested stack-trace of an throwable.</p>
	 *
	 * @param throwable the <code>Throwable</code> to be examined
	 * @return the nested stack trace, with the root cause first
	 * @since 2.0
	 */
	public static String getFullStackTrace(Throwable throwable) {
		StringWriter sw = new StringWriter();
		PrintWriter pw = new PrintWriter( sw, true );
		Throwable[] ts = getThrowables( throwable );
		for ( int i = 0; i < ts.length; i++ ) {
			ts[i].printStackTrace( pw );
			if ( isNestedThrowable( ts[i] ) ) {
				break;
			}
		}
		return sw.getBuffer().toString();
	}

	//-----------------------------------------------------------------------
	/**
	 * <p>Captures the stack trace associated with the specified
	 * <code>Throwable</code> object, decomposing it into a list of
	 * stack frames.</p>
	 *
	 * @param throwable the <code>Throwable</code> to exaamine, may be null
	 * @return an array of strings describing each stack frame, never null
	 */
	public static String[] getStackFrames(Throwable throwable) {
		if ( throwable == null ) {
			return ArrayHelper.EMPTY_STRING_ARRAY;
		}
		return getStackFrames( getStackTrace( throwable ) );
	}

	/**
	 * <p>Functionality shared between the
	 * <code>getStackFrames(Throwable)</code> methods of this and the
	 * {@link org.apache.commons.lang.exception.NestableDelegate}
	 * classes.</p>
	 */
	static String[] getStackFrames(String stackTrace) {
		String linebreak = LINE_SEPARATOR;
		StringTokenizer frames = new StringTokenizer( stackTrace, linebreak );
		List list = new LinkedList();
		while ( frames.hasMoreTokens() ) {
			list.add( frames.nextToken() );
		}
		return ( String[] ) list.toArray( new String[list.size()] );
	}

	/**
	 * <p>Produces a <code>List</code> of stack frames - the message
	 * is not included.</p>
	 * <p/>
	 * <p>This works in most cases - it will only fail if the exception
	 * message contains a line that starts with:
	 * <code>&quot;&nbsp;&nbsp;&nbsp;at&quot;.</code></p>
	 *
	 * @param t is any throwable
	 * @return List of stack frames
	 */
	static List getStackFrameList(Throwable t) {
		String stackTrace = getStackTrace( t );
		String linebreak = LINE_SEPARATOR;
		StringTokenizer frames = new StringTokenizer( stackTrace, linebreak );
		List list = new LinkedList();
		boolean traceStarted = false;
		while ( frames.hasMoreTokens() ) {
			String token = frames.nextToken();
			// Determine if the line starts with <whitespace>at
			int at = token.indexOf( "at" );
			if ( at != -1 && token.substring( 0, at ).trim().length() == 0 ) {
				traceStarted = true;
				list.add( token );
			}
			else if ( traceStarted ) {
				break;
			}
		}
		return list;
	}

}
